Sun following device

ABSTRACT

A heliostat has an axle parallel to the earth&#39;&#39;s axis which is driven to revolve once each 48 hours, the axle having two oppositely disposed mirrors mounted thereon to each reflect the sun&#39;&#39;s light on alternate days, the mirrors being automatically adjusted to compensate for the declination of the sun by means of gears and a cam driven by the rotation of the axle.

UnitedStates Patent Botskor 1 Apr. 18, 1972 54] SUN FOLLOWING DEVICE1,632,254 v /1927 Vinogradov ..353/3 2,022,144 11/1935 Nicolson.......353 3 [7 Inventor: Ivan Bolskor, Brelsgan, Gemany 2,646,720 7/1953Poliansky 353;: [73] Assignees: Tibor Horvath; George Kalnay, a part intwrest to each Primary Examiner-Harry N. Harman Attorney-J. Bradley Cohn[22] Filed: June 26, 1969 21 Appl. No.: 836,917 1 f S I A heliostat has.an axle parallel to the earths axis which is driven to revolve once each48 hours, the axle having two op- U.S. p i ly di p d mirrors mountedhereon to e reflect the [51] 21/00 sun's light on alternate days, themirrors being automatically [58] Field of Search ..353/3; 350/299, 6 j dto tef r the declination of the sun by means of gears and a cam drivenby the rotation of the axle. [56] References Cited UNITED STATES PATENTS9 Claims, 18 Drawing Figures 326,711 I 9/1885 Braune .353/3 PATENTEDAPR18 I972 3.656.844

SHEET 1 BF 5 PLANE OF THE EQUATOR wiitl "I CELESTIAL AXISEV EARTH AXISnvvm' '1 m. IVAN BOTSKOR PATENTEDAFR 18 I972 SHEET 3 BF 5 INVI'JNI'OH.IVAN BOTSKOR ATTORNI'IY PATENTEDAPR 18 1972 SHEET BF 5 INVPINIUR.

IVAN BOTSKOR ATI'ORNEY PATENTEDAFR 18 1972 SHEET 5 BF 5 fryf5.

VIII/Ill]! IVAN' BOTS KOR sun FOLLOWING DEVICE BACKGROUND OF THEINVENTION Heliostats to reflect the light of the sun to dwellings andfor other purposes are known. This invention provides a fully automaticheliostat which is less costly, easier to orient, and more effective andreliable in use.

BRIEF DESCRIPTION OF THE DRAWING Fig l is a plan view of an exaggeratedorbit of the earth about the sun;

FIG. 2 is a diagram showing the positions of the plane of the apparentrotation of the sun during different seasons;

FIG. 3 is a diagram showing the position of the plane of the equator inrelation to the plane of the apparent rotation of the sun;

FIG. 4 is a diagram showing the divergence of the celestial axis and theearths axis;

FIG. 5 is a diagram of flat mirrors positioned to reflect light fromthree directions in a single direction;

FIG. 6 is a side view of a heliostat according to my invention with itsaxle housing partly broken away in section and with its mirrors shown indotted lines in alternate for declination;

FIG. 7 is a vertical longitudinal section through the heliostat housing;FIG. 8 is a transverse longitudinal section through the heliostathousing;

FIG. 9 is a section taken on line 99 of FIG. 7;

FIGS 10-13 show the heliostat of this invention being used with minorsto illuminate buildings;

FIGS. 14 and show, respectively, the conduction of light through a lightpipe and through a fiber optical bundle; and

FIGS. 16-18 show the heliostat of this invention being used toilluminate buildings using light pipes or optical bundles.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, the earthmakes a yearly orbit about the sun describing an ellipse having the sunat one of its foci. For this reason, the apparent speed of rotation ofthe earth about the sun is greater at one portion of its orbit. As shownin FIGS. 2 and 3, the sun, as seen from the earth, moves on thecelestial axis with its plane of rotation varying continually throughoutthe year with respect to the plane of the equator. This variation isknown as declination which is the angular value of the differencebetween the plane of the apparent rotation of the sun and the plane ofthe equator. The declination varies between plus and minus 23 degreesand 27 minutes. FIG. 4 shows the divergence between the axes of rotationof the earth and its orbit about the sun.

FIG. 5 is a schematic diagram of the laws of light reflection from aflat mirror in positions M, M, and M The mirror in' position M and M hasthe perpendiculars N and N. In position M, the mirror reflects lightfrom A in the direction indicated by A. In position M, light from C isdirectly reflected back in the direction indicated by C. In position Mthe mirror reflects light from B in the direction indicated by B. Thusit may be seen that in order for a mirror to reflect light in the samedirection from sources moved through 180, the mirror need only be movedthrough 90". The heliostat of this invention thus moves its mirrors atone-half the apparent speed of rotation of the sum to reflect its raysin one direction.

FIG. 6 shows the heliostat of this invention. A housing 4 has an axle 3projecting from it which is driven to make one revolution each 48 hours.Housing 4 is mounted on a base 11 by means of a hinge l2 and a jack 13having a height adjusting wheel 14. This mounting of housing 4 allowsaxle 3 to be aligned with the axis of the earth. Flat mirrors 1 and 2are attached to each side of axle 3 by means of the arms 5, 6, 7 and 8.The mirrors 1 and 2 are pivotally attached to the arms 5 and 6 by theclevis connections 9 and 10 so that they may be axially aimed.

Housing 4 has a protruding axle housing 15 which rotatably mounts axle 3within a sleeve 16. Sleeve 16 has a gear 17 positions adjusted mountedon it so that right 'or left hand rotation of sleeve 16 relative to axle3 will urge the rack gear sections 18 and 19 inward or outward. Sincethe rack gears 18 and 19 are fixed to the arms '7 and 8 which areconnected to mirrors 1 and 2 by the pivots 20 and 21, relative rotationof sleeve 16 will axially aim mirrors 1 and 2. An alternate position ofthese elements is shown in dotted lines and indicated by the referencenumerals 1, 2', 7', 8', l8 and 19'.

Since the earth turns on its axis once in 24 hours, axle 3 makes onecomplete revolution each 48 hours to position mirrors l and 2 to reflectlight on alternate days. Since the angle of incidence of the sun's rayson the flat mirrors 1 and 2 is equal to the angle of reflection, theaxial aiming of the mirrors 1 and 2 need only be one-half the angle ofdeclination to follow the sun.

Referring now to FIGS. 7, 8 and 9, a synchronous motor 22 drives areduction gear transmission 23 which, by means of gears 24 and 70, drivethe drum 25 having the gear 71 formed thereon. Drum 25 is mounted onaxle 3 and drives it. An internal gear 74 is mounted in housing 4 aboutone end of drum 25. Gear 75 extends through drum 25 to mesh withinternal gear 74 and thus be driven as drum 25 rotates. Gear 75 ismounted on transmission 26 which rotates cam 27 through one completerevolution each year.

Rack gear 30 is slidably disposed in guide 31 and urged toward cam 27 byspring 29 so that roller 28 rides on cam 27. Thus rotation of cam 27moves rack gear 30 to drive pinion 32 and gear 33 to drive gear 34 whichis mounted on sleeve 16. In this manner,rotation of cam 27 axially aimsthe mirrors 1 and 2. Suitable high precision bearings are provided forall moving parts.

Since the flat mirrors 1 and 2 of the heliostat may be about 60 metersfrom the first surface that reflects them, divergence between the actualrotation of the earth and the apparent rotation of the sun may becompensated by stopping the motor 22 for short intervals with a timer(not shown) for a maximum of 2 minutes every 4 days to a minimum of 2minutes every seven days.

As shown in FIG. 10, a heliostat according to this invention has beenmounted on a building to reflect light to the mirrors 35 and 36 in theapartment 37 in building 81. FIG. 11 shows light from a heliostat beingreflected from three fixed and aimed mirrors 38, 39, and 40 intoapartments 41, 42 and 43 in building 82. As shown in FIG. 12, aheliostat on building 83 reflects light to the convex mirrors 44 and 45and the flat mirror 46 to light the lower apartments 47-39 in building84 and apartments 50-52 in building 83. FIG. 13 shows how both convexmirrors 53 and concave mirrors 54 may be used to direct heliostat lightinto apartments.

FIGS. 14 and '15 show a light pipe of Lucite or glass and a fiberoptical bundle 86 both of which pass light therethrough. FIG. 16 shows aheliostat 87 having parabolic mirrors 55 and 56 which direct light intothe flared end 57 of a light pipe 58. As may be seen in FIG. 18, pipe 58terminates at 59 to light apartment 88 in building 89. FIG. 17 shows aheliostat 87 directing light into the end of a light pipe 58 which issplit to light the apartments 91-96 in building 90 with the lightemitting ends 59-64.

While this invention has been shown and described in the best formsknown, it will nevertheless be understood that these may be modifiedwithout departing from the spirit and scope of the invention except asit may be more limited in the appended claims wherein I claim:

1. A heliostat comprising, in combination, an axle aligned with theearths axis, means rotating said axle axle in 48 hours, means mountingtwo mirrors on opposite sides of said axle, each mirror reflecting thelight of the sun on alternate days, each mirror moving with said axle atone-half the apparent speed of rotation of the sun, and means axiallyaiming said mirrors on said axle compensating for declination.

2. The combination according to claim 1 with the addition of first armsfixed to extend from opposite sides of said axle, said mirrors beingpivotally mounted on said first arms, said 3. The combination accordingto claim 2 wherein said means axially aiming said mirrors comprises asleeve rotatably mounted on said axle, a first gear mounted on saidsleeve, rack gear sections engaging opposite sides of said first gear,second arms connecting said rack gear sections to said mirrors, andmeans rotating said sleeve relative tosaid axle to axially aim saidmirrors.

4. The combination according to claim 3 wherein said means rotating saidaxle comprises a drum disposed about said axle rotating said axle,asynchronous motor, and a first reduction gear transmission driven byonce in 48 hours.

5. The combination according to claim 4 wherein said means rotating saidsleeve relative to said axle comprises a second reduction geartransmission mounted in said drum, means driving said secondtransmission on rotation of said drum, a cam driven by said secondtransmission, a cam follower engaging said cam, and means responsive tomotion of said can follower rotating said sleeve relative to said axle.

said motor rotating said drum 6. The combination according to claim 5wherein said means driving said second transmission on rotation of saiddrum comprises an internal gear disposed about said drum and a secondgear mounted on said second transmission, saidsecond gearengaging saidinternal gear driving said second transmission.

7. The combination according to claim 6 wherein said means responsive tosaid cam follower rotating said sleeve comprises a rack fixed to saidcam follower, means slidably mounting said rack, means urging said rackand said cam follower toward said cam, and a pinion on said sleevemeshing with said rack, said cam sliding said rack rotating said pinionand thereby said sleeve relative to said axle.

8. The combination according to claim 1 with'the addition of fixedmirrors reflecting light from said heliostat to light dwellings.-

9. The combination according to claim 1 wherein said heliostat hasparabolic mirrors and with the addition of light conducting meansconducting light from said heliostat to light dwellings.

Patent No. 3, 56,844 Dated April 18, 1972 Ivan Botskor Inventor(s) v Itis certified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column 1, line 63, "sum" should read --sun--.

Claim 1, column 2, line 67, the phrase "means rotating said axle axle in48 hours," should read --means rotating said axle once in 48 hours,--.

Signed and sealed this 19th day of September 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOT'I'SCHALK Attesting Officer Commissionerof Patents FORM PO-1050 (10-69) USCOMM-DC 60376-P69 a u.s. GOVERNMENTPRINTING OFFICE: lass 0-366-334

1. A heliostat comprising, in combination, an axle aligned with the earth''s axis, means rotating said axle axle in 48 hours, means mounting two mirrors on opposite sides of said axle, each mirror reflecting the light of the sun on alternate days, each mirror moving with said axle at one-half the apparent speed of rotation of the sun, and means axially aiming said mirrors on said axle compensating for declination.
 2. The combination according to claim 1 with the addition of first arms fixed to extend from opposite sides of said axle, said mirrors being pivotally mounted on said first arms, said means axially aiming said mirrors pivoting said mirrors on said first arms.
 3. The combination according to claim 2 wherein said means axially aiming said mirrors comprises a sleeve rotatably mounted on said axle, a first gear mounted on said sleeve, rack gear sections engaging opposite sides of said first gear, second arms connecting said rack gear sections to said mirrors, and means rotating said sleeve relative to said axle to axially aim said mirrors.
 4. The combination according to claim 3 wherein said means rotating said axle comprises a drum disposed about said axle rotating said axle, a synchronous motor, and a first reduction gear transmission driven by said motor rotating said drum once in 48 hours.
 5. The combination according to claim 4 wherein said means rotating said sleeve relative to said axle comprises a second reduction gear transmission mounted in said drum, means driving said second transmission on rotation of said drum, a cam driven by said second transmission, a cam follower engaging said cam, and means responsive to motion of said cam follower rotating said sleeve relative to said axle.
 6. The combination according to claim 5 wherein said means driving said second transmission on rotation of said drum comprises an internal gear disposed about said drum and a second gear mounted on said second transmission, said second gear engaging said internal gear driving said second transmission.
 7. The combination according to claim 6 wherein said means responsive to said cam follower rotating said sleeve comprises a rack fixed to said cam follower, means slidably mounting said rack, means urging said rack and said cam follower toward said cam, and a pinion on said sleeve meshing with said rack, said cam sliding said rack rotating said pinion and thereby said sleeve relative to said axle.
 8. The combination according to claim 1 with the addition of fixed mirrors reflecting light from said heliostat to light dwellings.
 9. The combination according to claim 1 wherein said heliostat has parabolic mirrors and with the addition of light conducting means conducting light from said heliostat to light dwellings. 